Advances in semiconductor processing and logic design have permitted an increase in the amount of logic that may be present on integrated circuit devices. As a result, computer system configurations have evolved from a single or multiple integrated circuits in a system to multiple hardware threads, multiple cores, multiple devices, and/or complete systems on individual integrated circuits. Additionally, as the density of integrated circuits has grown, the power requirements for computing systems (from embedded systems to servers) have also escalated. Furthermore, demanding software, and its requirements of hardware, have also caused an increase in computing device energy consumption. In fact, some studies indicate that computing devices consume a sizeable percentage of the entire electricity supply for a country, such as the United States of America. As a result, there is a vital need for energy efficiency and conservation associated with integrated circuits. These needs will increase as servers, desktop computers, notebooks, ultrabooks, tablets, mobile phones, processors, embedded systems, etc. become even more prevalent (from inclusion in the typical computer, automobiles, and televisions to biotechnology).
In addition, there are various constraints placed on an integrated circuit with regard to the level at which it can operate, both as to operating frequency and voltage (as well as other possible constraints). Many of these constraints are placed by the manufacturer of an integrated circuit and can relate to parameters such as a thermal design point (TDP), which is a maximum heat dissipation that an associated cooling system can handle for the integrated circuit (and thus the average maximum power that the integrated circuit can consume). The integrated circuit can similarly be constrained to operate at a maximum available frequency, maximum available voltage and so forth.
Depending on the environmental conditions at which an integrated processor is operating and its processing load, a processor may be constrained to operate at no greater than an electrical design point (EDP) which is a maximum power consumption level (actually current, translated to power) that the integrated processor as a whole is not allowed to exceed, even instantaneously. While this EDP is set on manufacture for different operating conditions (e.g., temperature and so forth), as greater amounts of cores and other circuitry are present on a processor or other integrated circuit, which can potentially operate at different power consumption levels, it becomes difficult to monitor and determine a dynamic EDP for the processor.